It is common practice for a steam generator to be provided with an ash hopper that discharges onto an endless conveyor, such as a submerged scraper chain conveyor. The objectionable escape of gas and dust can be inhibited by a seal provided between the two and the present invention is concerned to provide means by which a gap between a hopper outlet and a conveyor below it may be closed.
According to the present invention, there is provided an apparatus comprising an ash hopper and an endless conveyor extending below the hopper and running beside a wall that bounds the path of the conveyor, means closing a gap between the wall and a strip fixed to, or incorporated in, the hopper and extending lengthwise of the wall, the means including a flexible impermeable band extending along the wall and fixed along one edge to the wall or the strip, a beam that is fixed along the other edge of the band, and clamps acting on the beam by operation of which the beam may be withdrawn from, and held in engagement, with the strip or the wall.